Skin modifier problems

[Blaine]

I'm using the skin modifier to rig my model to the biped. I'm not sure if my problem is the geometry or the skin modifier. The knee & ankle were really easy but the thigh & pelvis is proving quite difficult. Do you know why?

[Aurelius]

Its not an issue of geometry ... its an issue of bones. Regarding pelvis area the solution for this classic situation is one of 2 things to do:

a) You use additional bones to drive these areas and fix the loss of volume.
b) You use a helper and add it to the skin as a bone and tweak the envelops.